my car blew a turbo a few months ago so i parked the car in my driveway until i could get a turbo and all the parts i needed to get the car back together.

i got a new turbo and installed it. when i tried to fire up the car it started flooding badly, to the point where a steady drip of fuel is coming from the exhaust. I already checked out a few sensors and still can't seem to correct the issue.

1986 base model car. full t2 drivetrain (s4)

3" exhaust, fmic, rising rate fpr, boost controller. ran great before blowing the turbo and sitting. Any ideas?

thanks in advance for your help

 

Wow, fuel dripping from the exhaust? Wicked.... maybe you've got an injector stuck open/ clogged up? Pull the plugs, put a little oil in there and then get some new plugs (or let them dry) and try to start her up and get it running. Or use some carb cleaner and see if that gets her started.

 

i have gone back and checked every sensor, pin by pin voltage to the ecu and compression tested the engine. i have also removed and tested the injectors for leakage and resistance. if i use atf in the plug holes and clean the plugs i can get it to run for about 5 seconds but dies immediately. any ideas?

 

Check the Air Flow Meter? If it's out the car will run after start for a very brief time (3-5 seconds) Check for vac leaks? Check that the fuel pump is working/getting adequate power?Sorry for the generic responses, but that's all I can think of....

 

Well your the only one willing to give me some help so it is greatly appreciated.

I will go back and check everything again, but i already checked the afm. its good.
Already checked the pump, good volts, good flow.
As for vac leaks, i have yet to find any.
I am starting to think this may be an issue with my ecu. I bought it used and the front is scratched and gouged. i found one for pretty cheap so i think i am going to try that.

 

i am completely amazed at the lack of responses that this thread has gotten.

 

when you said that your turbo blew up,what really went bad with it?a motor that drips fuel out of the exhaust ports means that something is wrong with the injection sistem and somehow is getting to much fuel,not getting ignited or not getting compress,if you know for sure that the fuel system is fine is time to start looking at other things,are you sure your seals are fine?maybe stock in place cause of the time the motor wasn,t running?Did the motor swallow pieces of the turbine blade?

 

i can clarify some of this for you. there is absolutely nothing wrong with my motor. it has 50 psi on each bump during a compression test and builds 105psi altogether on front and rear housings. it has excellent spark(msd on trailing coil). fuel pressure is ok. turbo blew up the bearing. no pieces of turbo in the motor.

 

honestly i feel i must have a bad ecu, or some reason why the ecu is opening the injectors too much. one thing i think might be causing an issue is the length of my battery cables(rerouted behind driver seat). if the voltage drop across the cable is too great maybe when the starter gets a big load it resets the ecu and pulses too many times. is this possible?

 

I'm no electrician, but I don't think the voltage drop from the cables would be sufficient to alter the ECU's acticities unless they were 30' long. I am often wrong however, and don't mind being corrected, lol. S4 ECU's are cheap, get another and see if it helps, but then again throwing money at it only helps with strippers.

 

If I were you i'd check your secondaries' orings and rubber fittings to the fuel rail. When my pulsation dampner went out it knocked mine out of whack and I left a 20' trail of gas from the pipes. Also since you say s4 - if your pd has not been replaced either replace it now or do the banjo bolt job, but the banjo is still under debate.

 

not trying to high jack the thread here but i swap out my sec's to some s4 720's and my car wont start could it it be because the ecu isint reading correct voltage on the injectors ?

 

I believe that is a thread jack. check and see if you need high impedance or low impedance and use the correct resistor pack...

 

what do you mean with the secondary injectors exactly. i already had them out a few days ago and put new o-rings on the top where it meets the rail. do you mean that they could be in the rail too deep or leaking to the atmosphere. or am i mistaken and they would leak into the intake?

 

what would cause the car to run for about 5 seconds and then flood? this seems very strange to me.

all temp sensors are ok.
afm checked out.
tps ok and adjusted.
plugs ok.
compression good.
great spark.
good cas.(spare one, tried swapping them, no difference)
couldnt find any vacuum leaks.
leakage tested injectors, injectors ok.
boost sensor ok.
fuel pressure ok.

if i put atf in the plug holes and clean the plugs i can get the car to fire up for a few seconds but then floods almost immediately. the car doesnt run good but it does run when i can get it to fire up.

i cut the wire harness open and checked for shorts. i can't seem to find anything. i also switched out my ecu , afm, and map sensor with my old na parts. still does the exact same thing so i don't think i have a bad ecu.

what could i be missing?

i also felt i needed to say that this car has an s4 na harness altered for a turbo engine, dont know if that would even make a difference but for all i know it does so there you have it.

 

Have you checked the voltage for the AFM at the ECU? PUll the pin and see that it is in spec there as well. The engine uses a fuel map in ECU for the first few seconds at start-up then switches to the AFM and uses it to determine fuel afterwards.

 

i checked it with the afm closed. i will check it again, thanks

 

honestly i am at a loss for what to look for next. the afm input to the ecu is good....
one thing i noticed that is strange is, when the key is on and not cranking, the logicon unit's lights don't light. could a power loss cause an issue like this?
i was under the impression that all of these lights should light up with the key on to show that the bulbs are ok. strangely, this is an intermittent problem.

 

any ideas?

 

come on, no ideas?

 

try new injectors?

 

i think that would probably be expensive, but i guess if it's the next step. anyone know where to get any cheap injectors?

 

i have a set of na injectors. maybe i should swap them out and try it. they're smaller but they should still work.

 

Sounds like a very large air leak was created when you swapped the turbo out. Like the TID duct cracked/off etc.

Sure it ran ok prior to the turbo problem? Sure the afm plug is on the afm? Make a fuel cut switch to help yourself out. Pouring oil into the engine to start it is something that shouldn't be happening.

Fuel dripping out the exhaust indicates a fuel injector leaking badly imho. But you checked that.

The water thermosensor on the waterpump housing if off will cause not enough fuel during a COLD start. But you have fuel dripping out the exhaust.

I'd disable the fuel pump. Then spray starter fluid into the snorkel in front of the afm for two seconds and no more. Start the engine several times doing that to confirm ??? heck I don't know. That it'll start each time I guess. Never use starter fluid to KEEP an engine running. KNOCK.

The turbo intake duct cannot have cracks where it attached to the turbo or anywhere else. The checkvalve and bov have to be installed in the TID. Those holes in the TID can't be left open.

If the water thermo sensor is disconnected, then LESS fuel will be delivered duing START. Considerably less fuel.

 

the strange thing is that i cant seem to find anything like that. the afm is working ok, moving just like it should. It ran fine before the turbo went out.